“. . .you got marijuana in my lead.”
Two great tastes that do not go great together (with apologies).
A concise but fascinating medical detective story appears in the letters of this week’s (10 Apr 2008) issue of the New England Journal of Medicine (free full text at the time of this posting.).
An astute group of physicians at Leipzig Hospital in Germany noted a local surge of young people presenting with classic symptoms of lead poisoning – 29 patients aged 16 to 33 over the course of 3-4 months. Patients exhibited symptoms ranging from abdominal cramps, nausea, and “Burton’s line” to hematologic pathologies such as anemia and basophilic stippling (overview). Burton’s line, illustrated here in another NEJM image from a lead poisoning case, results from “the reaction of circulating lead with sulfur ions released by oral microbial activity [that] may cause the deposition of lead sulfide at the interface of the teeth and gums.”
In another hospital in Leipzig, one patient was so severely poisoned that they had severe encephalopathy with hallucinations and permanent palsy in one forearm.
None of the patients were in any industry, such as lead-smelting, where today’s rare cases of lead poisoning still occur. Instead, they were young smokers with body piercings, either students or unemployed.
The diagnosis was quickly established, and chelation therapy was effective, but despite great efforts by health authorities and police, the source of lead could not be identified.
Yes, this is the one evidence-based indication for chelation therapy, usually with aminocarboxylate (calcium EDTA) or sulfur-containing compounds (2,3-dimercaptosuccinic acid; DMSA; succimer; Chemet®) to complex the lead with very high affinity and enhance its urinary excretion.
What else was common to these patients?
Upon further questioning, all patients admitted to smoking marijuana. Was this a case of marijuana being grown in soil with high lead content?
When some patients provided the investigators with samples of their stash, one showed visual evidence of lead particles (photo).
At this point, we involved the police, and a full criminal investigation was begun. Health authorities immediately started an anonymous screening program for marijuana users. After 2 weeks, 145 persons had used this service. A total of 95 of these persons had blood lead levels that required treatment (>25 μg per deciliter), and some of these persons had dangerous levels of lead (>80 μg per deciliter).
The lead doping of dope, as it were, was so pervasive in the area that 66% of those screened had clinical lead poisoning. By now, you can probably guess the probable reason for lead in the marijuana:
The current working hypothesis of the police is that because of its high specific gravity and inconspicuous grayish color, lead was used to increase the weight of street marijuana sold by the gram and thereby to maximize profits among dealers. In the material that was obtained, the lead content on average was 10% by weight, which translates into a profit increase of approximately €1,000 ($1,500.00) per kilogram of marijuana.
While exposure to lead has decreased worldwide, physicians should renew their familiarity with the clinical signs of acute lead poisoning and include this possibility in the differential diagnosis of neurological symptoms in suspected marijuana users. You can bet that the economic aspect of this story will resonate with drug dealers, if it hasn’t already, and I wouldn’t surprised if lead poisoning becomes more widespread among marijuana users.
Lead particles smoked in a joint, which can have a core temperature of 1200°C, are very effectively absorbed in the respiratory tract. The medical community, including pediatricians, should consider adulterated marijuana as a potential source of lead intoxication.
And while we would never condone the use of illegal substances among our readers or their friends and other loved ones, a visual inspection of marijuana supplies for lead particulate would be advisable for recreational users.
Mega props to our colleagues in Germany at University Hospital Leipzig and Dialysis Center Grimma for their superb detective work and communication of these cases with the international medical community.
Busse, F., Omidi, L., Leichtle, A., Windgassen, M., Kluge, E., Stumvoll, M. (2008). Lead Poisoning Due to Adulterated Marijuana. New England Journal of Medicine, 358(15), 1641-1642. (free full text at the time of this posting.)